This invention relates to musical instrument strings, and deals more particularly with a method for making such strings of the type having beads at one end thereof for use in attaching the strings to musical instruments. It also relates to the construction of end beads for use in practicing the method.
As to general subject matter, this invention is related to copending U.S. Pat. Application Ser. No. 699,707, filed June 25, 1976, now abandoned, which shows another method for fixing beads to musical instrument strings. As explained in the copending application, strings for many musical instruments commonly carry a bead at one end thereof, in the shape of a ball, cylinder, ferrule or the like, to provide an enlargement on the string for use in attaching it to a compatibly designed bridge or tailpiece. At present, a conventional way of attaching a string to a bead is to loop the string around an externally waisted portion of the bead and to then twist the short length of the loop around the longer length. This attachment method is a relatively difficult and time-consuming one whether done by hand or machine and results in a twisted portion of the string adjacent the bead which is not only somewhat unsightly but also of a larger diameter than the remaining untwisted portion of the string. Also, after the bead is attached to the string, if the string is tested by applying a tension load through the bead to the string, it usually will be found to have a breaking strength substantially less than a similar unbeaded string.
The general object of this invention is, therefore, to provide a simple and efficient method for attaching end beads to musical instrument strings and which method, particularly under high volume or mass production conditions, enables beads to be attached to strings at relatively low cost per string. In keeping with this object, a still further object is to provide an attachment method which avoids the need for either hand looping and twisting operations or relatively complex machinery to mechanically perform such looping and twisting.
A further object of this invention is to provide a method for attaching an end bead to a musical instrument string which method results in a string having a higher breaking strength than similar strings with beads attached by twisting.
Another object of the invention is to provide a bead attachment method of the foregoing character whereby the resulting finished string has an attractively neat appearance and does not include any portion where the main wire of the string is twisted upon itself.
Another object of this invention is to provide a bead for use in accordance with the method of the invention and which bead is particularly immune to cracking or other failure during the step of its deformation.
The method and bead of this invention may be applied to either an unwound string in which the string consists merely, except for the bead, of a single metallic wire, or they may also be applied to a wound string consisting, apart from the bead, of a metallic core wire carrying a helically wound cover wire or wrap. Hereinafter, the term "main wire" is used to refer to the wire to which the bead is fixed whether it be the sole wire of an unwound string or the core wire of a wound string.